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Dates in Oracle atomic digit 18 stored in numeral coiffe.Each hold off represents the century, year, month, day, hours, minutes, and seconds.The default witness format is DD-MON-YY.Using the SYSDATE function, you buns display the real date and conviction.You erect do SYSDATE as you would use any other column name.In order to view the time you will need to use the TO_CHAR function along with a format mask which includes a time format element.For example, you arse display the live date by selecting SYSDATE from a table.You usually select SYSDATE from a tit table called DUAL.All users can access the DUAL table.It is owned by the SYS user.It consists of maven column known as DUMMY, and one row with the mensurate X.When you want to return a value - not necessarily a date - once only, the DUAL table is useful.To display the topical date using the DUAL table, you use the command shown.And the output displays the current date.Dates are stored as numbers in the database, wh ich enables you to perform arithmetical calculations on them.You can add or get off the ground a number to or from a date for a resultant date value.You can cipher one date from another to find the number of days in the midst of them.You can also add hours to a date and time value.This is performed by dividing the number of hours in the time value by 24.Lets take a look at how you can manipulate dates.Lets say that you want to add and subtract days from the current date.To add one hundred days to the current date, you type the command shown.The result is displayed in the column SYSDATE+100.If you want to subtract 34 days from the current date, you type the command shown.The result is displayed in the column SYSDATE-34.Lets say you want to subtract the hire date from the current date - you type the command shown.The result shows the number of days surrounded by the current date and the hire date.Lets say you want to display dates in terms of weeks.To show the number of weeks each employee in department 10 has worked, you first subtract the hiredate from the current date.Then you divide the result by seven.You can use date functions in a similar sort to number functions to operate on Oracle dates.The MONTHS_BETWEEN function finds the number of months between two dates.The result is displayed as a numeric value.This is the only date function that does not return a date value.